One traditional approach to simulating electrical circuits is to use a SPICE (Simulation Program with Integrated Circuit Emphasis) transistor level circuit simulator created by the University of California, Berkeley in 1972, or one of its commercial transistor level circuit simulator variants such as SPECTRE™ by Cadence Design Systems, Inc., HSPICE™ by Synopsis, Inc., or ELDO™ by Mentor Graphics, Corp. A SPICE transistor level circuit simulator assumes that circuit waveforms can be efficiently approximated by low-order piecewise polynomials. The SPICE transistor level circuit simulator formulates a large set of equations representing the entire circuit. Over a small interval of time, the SPICE transistor level circuit simulator solves those equations repeatedly to find segments of the piecewise polynomials.
However, repeatedly solving equations of low-order piecewise polynomials over small time intervals on complex radio frequency (RF) circuits, large analog circuits, or large mixed-signal circuits may generally be slow and tedious in execution and/or exceed the capacity of today's computer systems.